Program providers such as multiple system operators (“MSOs”) deliver digital content and provide services to consumers over networks such as cable networks. Cable networks typically include headend reception and transmission equipment configured to distribute digital content/services to consumer network devices, such as set-top boxes, via encoded program streams carried over in-band channels.
In traditional cable networks, program streams are encoded using a combination of standard and proprietary protocols, and network interfaces are largely based on proprietary protocols. Moving Picture Experts Group (“MPEG”) protocols are generally used to encode content into data streams. Each data stream has an associated program identifier (“PID”) associated therewith, and multiple data streams are multiplexed into a single transport stream.
Information regarding the organization of the PIDs comprising the transport stream, is conventionally communicated to consumer network devices via service information messages transmitted on out-of-band (“OOB”) channels. PID organization information is defined by well-known relational addressing tables (that are also associated with PIDs within the transport stream) such as the Program Association Table (“PAT”) and Program Map Tables (“PMTs”). Other network-defined messages (often proprietary) are often delivered conventionally to consumer network devices on OOB channels. These message include service information messages that allow consumer network devices to efficiently decode MPEG's well-known relational addressing tables (for example, certain messages/tables defined by Motorola's DigiCipherII protocol), conditional access messages, electronic program guide messages, emergency alert system messages, and other generic messages. Many consumer network devices use hardware to filter messages received over OOB channels—for example, many set-top boxes manufactured by Motorola use hardware to filter messages relating to specific MPEG PIDs.
MSOs wish to create flexible network architectures—evidenced by the efforts of OpenCable™, a group of North American cable operators seeking to create a common platform for advanced interactive cable services—and prefer to rely on data communication technologies such as the Ethernet and Internet Protocol (“IP”), rather than an arrangement of proprietary network interfaces and protocols. The OpenCable™ effort has two key components: hardware specifications and software specifications. The hardware specifications define host devices (for example, set-top boxes) that include CableCARD™ modules/interfaces.
The software specifications, among other things, seek to standardize cable network interfaces. One such cable network interface is the interface for transporting messages over OOB channels between cable network headends and consumer network devices such as set-top boxes. The “DOCSIS® Set-top Gateway (DSG) Interface Specification,” issued by CableLabs® on Aug. 4, 2004 (the “DSG Specification”), defines an interface for transport of OOB messages over Internet Protocol between a set-top network controller and a set-top box. The DSG Specification is hereby incorporated by reference in its entirety for all purposes, as if set forth in full herein.
In converged IP and Ethernet systems, however, MPEG PIDs are not unique, making infrastructure, such as hardware used by consumer network devices to filter OOB messages relating to specific MPEG PIDs, of little use. And although certain advanced set-top boxes may be able to receive OOB messages in the manner set forth in the DSG Specification, without the ability to filter the IP OOB messages using existing hardware, they may be overwhelmed by the task of processing the large number of IP OOB messages required to manage the encoded data streams received over in-band channels.
There are therefore needs for methods and apparatuses for managing encoded data streams configured for broadcasting to consumer network devices within broadband communication systems, which methods and apparatuses use packet-based network protocol messaging for out-of-band communication with the consumer network devices, and which also allow the consumer network devices to receive relevant messages based on predetermined parameters of the encoding protocol.